Most older adults believe that their memory is not as good as it was when they were younger. They may misplace keys, blank on someone’s name, forget a phone number or have trouble finding words. A study in Finland documented that 76% of persons over the age of 60 years reported problems with their memory. It is known as age-associated memory impairment or AAMI, if there is no medical condition that causes this loss of memory. Age-associated Memory Impairment may indicate the risk for the eventual development of dementia and Alzheimer’s disease.
Due to the rapidly increasing number of elderly people in the world’s population, the development of treatments for age-associated memory impairment has become the top priority of public health. In this blog, we will introduce you to a study conducted by researchers at Northwestern University. These researchers used PEMF therapy to stimulate the brain in older adults to see if they could improve memory. The study was published in the journal Neurology on April 17, 2019.
The study group included 16 adults with normal age-related memory impairment, ages 64 to 80. Joel Voss, lead investigator and associate professor at Northwestern University Feinberg School of Medicine, said that “There is no previous evidence that the specific memory impairments and brain dysfunction seen in older adults can be rescued using brain stimulation or any other method.”
Voss’s team located the hippocampus which is responsible for memory and is known to shrink with age. The hippocampus plays a fundamental role in the formation of new memories about experienced events. “It’s the part of the brain that links two unrelated things together into a memory, like the place you left your keys or your new neighbor’s name,” Voss said. “Older adults often complain about having trouble with this.”
It is impossible to directly stimulate the hippocampus with noninvasive PEMF because it’s too deep in the brain for the magnetic fields to penetrate. So, Voss and colleagues chose to stimulate the parietal lobe. This parietal area overlies the area of the hippocampus and has high connectivity to the hippocampus. So, stimulation of this area is expected to influence the hippocampus to enhance memory.
Before they started the stimulation, younger people and 16 older adults (subjects) were given memory tasks in which they learned arbitrary relations between paired things to get a baseline, such as this object goes on this spot on the computer screen. Compared to the younger group who averaged around 55%, the older individuals were only correct about 40% of the time.
Stimulation was done using a PEMF device at about 10 pulses per second for 20 minutes in each session, over five consecutive daily sessions to the left side of the head. The researchers also used functional MRI (fMRI) of the brain to check how active a part of the brain is at a given time.
24 hours after the final stimulation, the subjects were given a new memory test in which they had to learn new arbitrary relations between paired things. “Older people’s memory got better up to the level that we could no longer tell them apart from younger people,” said Joel Voss. “They got substantially better.”
The study also used a fake placebo stimulation condition which did not improve memory.
This research shows that stimulation of the parietal area of the brain can impact the memory associated with the hippocampus. The other words, the magnetic field can penetrate deep enough into the brain through the parietal area into the hippocampal area to improve memory.
These results are exciting, not only ensuring the safety of PEMF stimulation, but also indicating that PEMF therapy actually improves age-related memory decline. Based on the results of this research, we would recommend daily use of a PEMF device to increase the function of the hippocampal area and encourage improvement in memory.
The study also provides a new idea for the treatment and prevention of dementia and Alzheimer’s disease. The sooner treatment begins, the better the results. Obviously, we can not get the same benefits as treating earlier age-related memory loss if Alzheimer’s disease has been established.
Network-targeted stimulation engages neurobehavioral hallmarks of age-related memory decline.
Neurology. 2019 May 14;92(20):e2349-e2354. Nilakantan AS, Mesulam MM, Weintraub S, Karp EL, VanHaerents S, Voss JL